Discontinuous ceramic phase reinforced high-temperature-resistant titanium-based composite material and preparation method thereof

Abstract

The invention belongs to the technical field of metal-based composite materials, and particularly relates to a discontinuous ceramic phase reinforced high-temperature-resistant titanium-based composite material and a preparation method thereof. A near-alpha type titanium alloy matrix with the nominal composition of Ti-6Al-6Zr-5Sn-1Mo-1Nb-1W-0.3 Si is provided, the content of all elements (such as 5%-7% of Al and 5%-7% of Zr) is precisely controlled, meanwhile, a TiC and TiB multi-dimensional discontinuous ceramic phase is introduced, B4C powder and the titanium matrix are subjected to in-situ reaction to generate, the content of a reinforced phase can be precisely regulated and controlled by adjusting the adding amount (0.5%-2%) of B4C, the limitation of a single reinforced phase is solved, and the strength of the reinforced phase is improved. The high-temperature performance and the mechanical performance are synergistically improved. Furthermore, a traditional reinforcement phase random distribution mode is broken through, a discontinuous reinforcement structure is constructed, the material strength and the high temperature resistance can be evenly improved in the multi-dimensional stress direction, and the requirements of aerospace thermal structure components under the complex load working condition are met.

Description

Technical Field

[0001] This invention belongs to the field of metal matrix composite technology, specifically relating to a discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material and its preparation method. Background Technology

[0002] Traditional high-temperature titanium alloys possess low density, high strength and toughness at room temperature, and excellent high-temperature performance. However, their maximum safe service temperature limit is close to 650℃, which is insufficient to meet the 750℃ temperature resistance requirements of thermal structural components in new spacecraft and hypersonic vehicles. Compared to traditional titanium alloys, adding ceramic reinforcing phases can increase their service temperature by 100℃~150℃, while combining the lightweight and high specific strength characteristics of titanium alloys with the high temperature resistance and high hardness advantages of ceramic reinforcing phases, making them a key material for lightweight and high-temperature development in the aerospace field. In existing technologies, ceramic-reinforced titanium matrix composites mainly employ continuous fiber reinforcement or single-morphology discontinuous reinforcing phases (particles, whiskers) designs, but the following technical bottlenecks exist: (1) High temperature performance limitations: The highest service temperature of traditional high temperature titanium alloys is close to 650℃, which cannot meet the requirements of the aerospace field for 750℃ temperature resistance; In existing ceramic reinforced titanium matrix composites, the continuous fiber reinforcement system is prone to generating brittle phases, which leads to a decrease in interfacial bonding strength, and the single-morphology discontinuous reinforcement phase has problems such as insufficient high temperature creep resistance or uneven dispersion.

[0003] (2) Design defects of reinforcing phase: Existing technologies mostly focus on the control of reinforcing phase size and morphology, ignoring the influence of spatial distribution on material properties. Randomly distributed reinforcing phases are difficult to achieve uniform performance improvement in multi-dimensional stress directions, which limits their application under complex load conditions.

[0004] (3) Insufficient preparation process: Some preparation methods (such as powder metallurgy) have problems such as complex process, high cost and difficulty in preparing large-size components, which restrict the large-scale application of materials.

[0005] (4) Continuous fiber reinforced system: Silicon carbide long fibers and titanium matrix are prone to interfacial reaction during high-temperature preparation to generate brittle phases such as TiSiC and Ti5Si3, which leads to a decrease in interfacial bonding strength and deterioration of the high-temperature performance of the material.

[0006] (5) Single-morphology discontinuous reinforcing phase: When only particle reinforcement is used, the material's high-temperature creep resistance is insufficient; when only whisker reinforcement is used, the whisker dispersion is poor and easily agglomerates, leading to stress concentration. Although Chinese patent literature (publication number: CN116121577A, publication date: 2023.05.16) improved the high-temperature hardness through AlO-ZrO eutectic particles, it did not solve the problem of balancing high-temperature creep and toughness.

[0007] (6) Unreasonable spatial distribution of reinforcing phase: Existing technologies focus more on the size and morphology control of reinforcing phase, ignoring the influence of its spatial distribution on material properties. Traditional randomly distributed reinforcing phases are difficult to achieve uniform strength and high temperature resistance improvement in multi-dimensional stress directions, which limits the application of materials under complex load conditions.

[0008] Therefore, developing a discontinuous ceramic phase titanium-based composite material with distribution characteristics and multi-morphological synergistic reinforcement to achieve synergistic improvement in high temperature resistance, mechanical strength and ductility has become an urgent technical problem to be solved in this field. Summary of the Invention

[0009] The purpose of this invention is to overcome the shortcomings of the prior art and provide a discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material and its preparation method.

[0010] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material. The alloy matrix of the titanium-based composite material, by mass percentage, comprises the following components: Al: 6%~8%, Zr: 5%~7%, Sn: 4%~6%, Mo: 0.8%~1.2%, Nb: 0.8%~1.2%, W: 0.8%~1.2%Mo, Si: 0.2%~0.4%, O: 0.1%~0.2%, C≤0.02%, N≤0.02%, H≤0.01%, with the balance being Ti, and other unavoidable individual impurity elements ≤0.05%, with a total impurity content ≤0.2%. The discontinuous ceramic phase is obtained by adding B4C to the alloy matrix and reacting it in situ with the titanium matrix, wherein the mass percentage of B4C is 0.5%~2%.

[0011] Furthermore, the discontinuous ceramic phase is titanium carbide (TiC) and titanium boride (TiB).

[0012] It should also be noted that the roles of each element in the above alloy matrix in the discontinuous ceramic phase reinforced high-temperature titanium matrix composite material are as follows: Al: Improves the high-temperature strength and oxidation resistance of titanium alloy matrix, and enhances the lattice stability of matrix through solid solution strengthening; Zr and Sn: Improve the creep properties of the matrix. Zr can refine the grains and Sn can reduce the activation energy of dislocation movement, which together improve the long-term high-temperature service stability of the material. Mo and Nb stabilize the β phase, improve the room temperature toughness of the material, and avoid matrix embrittlement caused by the addition of ceramic phases. W: Enhances the high-temperature hardness and wear resistance of the matrix. W has a large atomic weight, which can improve the matrix's resistance to high-temperature softening through interatomic forces. Si: promotes ceramic phase nucleation and optimizes the distribution of reinforcing phase. Si can form a transition layer with elements such as Ti and B, which improves the interfacial bonding between the reinforcing phase and the matrix. Strictly control the O content, limiting C: ≤0.02%, N: ≤0.02%, H: ≤0.01%: These elements can significantly deteriorate the key properties of titanium alloys through mechanisms such as interstitial solid solution strengthening, brittle phase precipitation, and lattice distortion, affecting their processing, forming, and service safety.

[0013] Secondly, the present invention provides a method for preparing the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material as described above, comprising the following steps: Step 1: Prepare the matrix alloy raw material package by mixing the raw materials according to the mass percentage of each element in the alloy matrix and mixing them evenly. Step 2: Weigh out B4C powder according to the mass percentage, wrap it with high-purity aluminum foil, and prepare a reaction source material package; Step 3: The matrix alloy raw material package and the reaction source material package are smelted multiple times, cooled and then taken out of the furnace to obtain a discontinuous ceramic phase reinforced high temperature resistant titanium matrix composite material ingot.

[0014] Preferably, the nominal composition of the alloy matrix of the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material is Ti-7Al-6Zr-5Sn-1Mo-1Nb-1W-0.3Si, with the following element contents by mass percentage: Al: 7.0%, Zr: 6%, Sn: 5%, Mo: 1%, Nb: 1%, W: 1%, Si: 0.3%, O: 0.15%, C≤0.02%, N≤0.02%, H≤0.01%, and the balance being Ti. This composition design ensures that the titanium alloy matrix is ​​a near-α-type alloy, meeting the dual requirements of high-temperature structural components for high-temperature stability and mechanical properties of titanium alloys.

[0015] Specifically, in step 1, the raw materials include grade 0 sponge titanium, high-purity aluminum briquettes, high-purity aluminum foil, sponge zirconium, titanium-tin master alloy, aluminum-molybdenum master alloy, aluminum-niobium master alloy, aluminum-tungsten master alloy, and aluminum-silicon master alloy.

[0016] Specifically, the titanium-tin master alloy is Ti80Sn, the aluminum-molybdenum master alloy is Al60Mo, the aluminum-niobium master alloy is Al75Nb, the aluminum-tungsten master alloy is Al50W, and the aluminum-silicon master alloy is Al10Si.

[0017] Specifically, in step 2, the B4C powder has a purity of ≥99.9% and an average particle size of 20 micrometers; the discontinuous ceramic phase in the high-temperature resistant titanium-based composite material is titanium carbide (TiC) and titanium boride (TiB), which is produced by in-situ reaction of boron carbide (B4C) and titanium matrix. The content of titanium carbide (TiC) and titanium boride (TiB) can be precisely controlled by adjusting the amount of boron carbide (B4C) powder added. The weight percentage of boron carbide (B4C) powder added is 0.5%~2%, which can be 0.5%, 1.0%, 1.5% and 2.0%. By adding the above-mentioned weight percentage of boron carbide (B4C) powder as the reaction source material, discontinuous ceramic phases with different volume fractions can be formed. TiC is uniformly distributed in the titanium matrix in the form of micron-sized particles (particle size 50~200μm), and TiB is distributed in the titanium matrix in the form of micron-sized fibers (diameter 1~3μm, length 20~50μm) in multiple spatial dimensions, forming a multidimensional reinforced structure. For every 0.5% increase in the amount of B4C powder added, the total volume fraction of TiC and TiB increases by 1.2%~1.5%.

[0018] Specifically, in step 3, a vacuum induction levitation melting furnace is used for melting. Before melting, the furnace cavity of the vacuum induction levitation melting furnace is evacuated to a vacuum degree ≤ 5.0 × 10⁻⁶. -3 The furnace is cleaned by introducing argon gas with a purity ≥99.999% at a pressure of 0.08~0.12MPa and holding the pressure for 4~6 minutes. Then, the furnace cavity is evacuated again to a vacuum degree ≤5.0×10⁻⁶. -3 Pa, and finally high-purity argon gas is introduced to a pressure of 0.04~0.06MPa to form a protective melting atmosphere and prevent elements such as oxygen, carbon, nitrogen, and hydrogen in the air from entering the alloy matrix.

[0019] Specifically, in step 3, a vacuum induction levitation melting furnace is used for melting: when the melting is performed twice, the induction power is set to 240~360kW and the time is 24~36min for the first melting to obtain a first ingot; the first ingot is flipped and inverted for a second melting, with the induction power set to 240~360kW and the time being 20~30min; after all melting is completed, the ingot is cooled to below 30℃ with the furnace at a cooling rate of 5~8℃ / min and then removed from the furnace to obtain a discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite ingot.

[0020] Furthermore, when the number of meltings is 3 or more, starting from the third melting, the induction power supply power of each melting is maintained at 240~360kW, and the time is shortened by 4~6min compared to the previous melting; after all meltings are completed, the furnace is cooled to below 30℃ with a cooling rate of 5~8℃ / min and then removed from the furnace to obtain a discontinuous ceramic phase reinforced high temperature resistant titanium matrix composite ingot.

[0021] Thirdly, the present invention provides the application of the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material as described above, or the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material prepared by the preparation method described above, in the thermal structural components of novel spacecraft and hypersonic vehicles.

[0022] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects: Innovative Material Composition: This invention proposes a near-α type titanium alloy matrix with a nominal composition of Ti-6Al-6Zr-5Sn-1Mo-1Nb-1W-0.3Si, precisely controlling the content of each element (e.g., Al: 5%~7%, Zr: 5%~7%), and simultaneously introducing multidimensional discontinuous ceramic phases of TiC and TiB, which are generated through in-situ reaction of B4C powder with the titanium matrix. The content of the reinforcing phase can be precisely controlled by adjusting the amount of B4C added (0.5%~2%), overcoming the limitations of a single reinforcing phase and synergistically improving high-temperature performance and mechanical properties.

[0023] Innovative Structural Design: This invention breaks through the traditional random distribution pattern of reinforcing phases and constructs a discontinuous reinforcing structure, which can uniformly improve the material strength and high temperature resistance in multiple stress directions, and adapt to the needs of aerospace thermal structural components under complex load conditions.

[0024] Innovative manufacturing process: This invention combines vacuum induction levitation melting technology with in-situ reaction technology, involving two melting processes (first melting at 300kW for 30 minutes; second melting at 300kW for 25 minutes) and strict control of the vacuum argon protective atmosphere (vacuum degree 5.0 × 10⁻⁶). -3 (Pa) ensures that the raw materials react fully and the elements are evenly distributed; compared with the powder metallurgy method for preparing titanium-based composite materials, this invention has a simpler preparation process and lower production cost, and can prepare large-size high-temperature resistant structural parts, which has a wider range of application prospects.

[0025] This invention significantly improves the high-temperature performance of titanium alloys by introducing a distributed, discontinuous ceramic phase into a near-α-type titanium alloy matrix, thereby discontinuously reinforcing the matrix. The invention combines vacuum induction melting with in-situ reaction technology to prepare high-temperature resistant titanium-based composite materials. By controlling the reaction type, the ceramic reinforcing phase can be selectively prepared. A specific crystal orientation relationship exists between the reinforcing phase and the matrix, resulting in good interfacial bonding and superior overall performance of the titanium-based composite material. Compared to powder metallurgy methods for preparing titanium-based composite materials, this invention offers a simpler preparation process and lower production costs, and can be used to fabricate large-size high-temperature resistant structural components, thus having broader application prospects. Attached Figure Description

[0026] The accompanying drawings are incorporated in and form part of this specification, and together with the description serve to explain the principles of the invention.

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material ingot of Embodiment 1 of the present invention; Figure 2 The microstructure of the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material of Example 1 of the present invention; Figure 3 The results of phase analysis of the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material in Example 1 of this invention are shown. Figure 4 This is the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite ingot of Embodiment 2 of the present invention; Figure 5 The microstructure of the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material of Example 2 of the present invention; Figure 6 The results of phase analysis of the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material in Example 2 of this invention are shown below. Figure 7 The tensile properties at 650°C, 700°C, and 750°C of the discontinuous ceramic phase reinforced high-temperature titanium matrix composites prepared in Examples 1 and 2. Detailed Implementation

[0029] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples consistent with some aspects of the invention as detailed in the appended claims.

[0030] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0031] This invention provides a discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material. The alloy matrix of the titanium-based composite material, by mass percentage, comprises the following components: Al: 6%~8%, Zr: 5%~7%, Sn: 4%~6%, Mo: 0.8%~1.2%, Nb: 0.8%~1.2%, W: 0.8%~1.2%Mo, Si: 0.2%~0.4%, O: 0.1%~0.2%, C≤0.02%, N≤0.02%, H≤0.01%, with the balance being Ti. Other unavoidable individual impurity elements are ≤0.05%, and the total impurity content is ≤0.2%. The discontinuous ceramic phase is obtained by adding B4C to the alloy matrix and reacting it in situ with the titanium matrix. The mass percentage of B4C is 0.5%~2%.

[0032] Furthermore, the discontinuous ceramic phase is titanium carbide (TiC) and titanium boride (TiB).

[0033] It should also be noted that the roles of the above elements in discontinuous ceramic phase reinforced high-temperature titanium-based composite materials are as follows: Al: Improves the high-temperature strength and oxidation resistance of titanium alloy matrix, and enhances the lattice stability of matrix through solid solution strengthening; Zr and Sn: Improve the creep properties of the matrix. Zr can refine the grains and Sn can reduce the activation energy of dislocation movement, which together improve the long-term high-temperature service stability of the material. Mo and Nb stabilize the β phase, improve the room temperature toughness of the material, and avoid matrix embrittlement caused by the addition of ceramic phases. W: Enhances the high-temperature hardness and wear resistance of the matrix. W has a large atomic weight, which can improve the matrix's resistance to high-temperature softening through interatomic forces. Si: promotes ceramic phase nucleation and optimizes the distribution of reinforcing phase. Si can form a transition layer with elements such as Ti and B, which improves the interfacial bonding between the reinforcing phase and the matrix. Strictly control the O content, limiting C≤0.02%, N≤0.02%, and H≤0.01%: These elements can significantly deteriorate the key properties of titanium alloys through mechanisms such as interstitial solid solution strengthening, brittle phase precipitation, and lattice distortion, affecting their processing, forming, and service safety.

[0034] Secondly, the present invention provides a method for preparing the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material as described above, comprising the following steps: Step 1: Prepare the matrix alloy raw material package by mixing the raw materials according to the mass percentage of each element in the alloy matrix and mixing them evenly. Step 2: Weigh out B4C powder according to the mass percentage, wrap it with high-purity aluminum foil, and prepare a reaction source material package; Step 3: The matrix alloy raw material package and the reaction source material package are smelted multiple times, cooled and then taken out of the furnace to obtain a discontinuous ceramic phase reinforced high temperature resistant titanium matrix composite material ingot.

[0035] Preferably, the nominal composition of the alloy matrix of the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material is Ti-7Al-6Zr-5Sn-1Mo-1Nb-1W-0.3Si, with the following element contents by mass percentage: Al: 7.0%, Zr: 6%, Sn: 5%, Mo: 1%, Nb: 1%, W: 1%, Si: 0.3%, O: 0.15%, C≤0.02%, N≤0.02%, H≤0.01%, and the balance being Ti. This composition design ensures that the titanium alloy matrix is ​​a near-α-type alloy, meeting the dual requirements of high-temperature structural components for high-temperature stability and mechanical properties of titanium alloys.

[0036] Specifically, in step 1, the raw materials include grade 0 sponge titanium, high-purity aluminum briquettes, high-purity aluminum foil, sponge zirconium, titanium-tin master alloy, aluminum-molybdenum master alloy, aluminum-niobium master alloy, aluminum-tungsten master alloy, and aluminum-silicon master alloy.

[0037] Specifically, the titanium-tin master alloy is Ti80Sn, the aluminum-molybdenum master alloy is Al60Mo, the aluminum-niobium master alloy is Al75Nb, the aluminum-tungsten master alloy is Al50W, and the aluminum-silicon master alloy is Al10Si.

[0038] Specifically, in step 2, the B4C powder has a purity of ≥99.9% and an average particle size of 20 micrometers; the discontinuous ceramic phase in the high-temperature resistant titanium-based composite material is titanium carbide (TiC) and titanium boride (TiB), which is produced by in-situ reaction of boron carbide (B4C) and titanium matrix. The content of titanium carbide (TiC) and titanium boride (TiB) can be precisely controlled by adjusting the amount of boron carbide (B4C) powder added. The weight percentage of boron carbide (B4C) powder added is 0.5%~2%, which can be 0.5%, 1.0%, 1.5% and 2.0%. By adding the above-mentioned weight percentage of boron carbide (B4C) powder as the reaction source material, discontinuous ceramic phases with different volume fractions can be formed. TiC is uniformly distributed in the titanium matrix in the form of micron-sized particles (particle size 50~200μm), and TiB is distributed in the titanium matrix in the form of micron-sized fibers (diameter 1~3μm, length 20~50μm) in multiple spatial dimensions, forming a multidimensional reinforced structure. For every 0.5% increase in the amount of B4C powder added, the total volume fraction of TiC and TiB increases by 1.2%~1.5%.

[0039] Specifically, in step 3, a vacuum induction levitation melting furnace is used for melting. Before melting, the furnace cavity of the vacuum induction levitation melting furnace is evacuated to a vacuum degree ≤ 5.0 × 10⁻⁶. -3The furnace is cleaned by introducing argon gas with a purity ≥99.999% at a pressure of 0.08~0.12MPa and holding the pressure for 4~6 minutes. Then, the furnace cavity is evacuated again to a vacuum degree ≤5.0×10⁻⁶. -3 Pa, and finally high-purity argon gas is introduced to a pressure of 0.04~0.06MPa to form a protective melting atmosphere and prevent elements such as oxygen, carbon, nitrogen, and hydrogen in the air from entering the alloy matrix.

[0040] Specifically, in step 3, a vacuum induction levitation melting furnace is used for melting: when the melting is performed twice, the induction power is set to 240~360kW and the time is 24~36min for the first melting to obtain a first ingot; the first ingot is flipped and inverted for a second melting, with the induction power set to 240~360kW and the time being 20~30min; after all melting is completed, the ingot is cooled to below 30℃ with the furnace at a cooling rate of 5~8℃ / min and then removed from the furnace to obtain a discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite ingot.

[0041] Furthermore, when the number of meltings is 3 or more, starting from the third melting, the induction power supply power of each melting is maintained at 240~360kW, and the time is shortened by 4~6min compared to the previous melting; after all meltings are completed, the furnace is cooled to below 30℃ with a cooling rate of 5~8℃ / min and then removed from the furnace to obtain a discontinuous ceramic phase reinforced high temperature resistant titanium matrix composite ingot.

[0042] To demonstrate the effectiveness of the present invention, the following embodiments are provided for verification.

[0043] Example 1 This embodiment provides a method for preparing a discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material, the specific steps of which are as follows: S1. The nominal composition of the titanium alloy matrix in the discontinuous ceramic phase reinforced high-temperature titanium matrix composite material is Ti-6Al-6Zr-5Sn-1Mo-1Nb-1W-0.3Si, with the following element contents: Al: 6.0%, Zr: 6%, Sn: 5%, Mo: 1%, Nb: 1%, W: 1%, Si: 0.3%, O: 0.15%, C≤0.02%, N≤0.02%, H≤0.01%. The ceramic phase is boron carbide (B4C) reacting with TiC and TiB in situ from the titanium matrix. The materials are batched according to the above nominal alloy composition and reinforcing phase type, with a total batch weight of [missing information]. 7000g, in this embodiment, the boron carbide (B4C) powder has a mass fraction of 0.5% and a weight of 35g. The remaining 6965g is the raw material required for the titanium alloy matrix, which consists of grade 0 sponge titanium, high-purity aluminum briquettes, high-purity aluminum foil, sponge zirconium, master alloy Ti80Sn, master alloy Al60Mo, master alloy Ti75Nb, master alloy Al50W, and master alloy Al10Si. The formulation strictly follows the nominal composition of the titanium alloy matrix. The master alloy and boron carbide (B4C) powder used in this embodiment are all wrapped with high-purity aluminum foil, and the mass of the high-purity aluminum foil is included in the total weight of aluminum in the alloy matrix.

[0044] S2. Place all raw materials into the copper crucible of the vacuum induction levitation melting furnace for melting, repeating the melting process twice. After loading the raw materials into the copper crucible, evacuate the furnace cavity to a vacuum level of 5.0 × 10⁻⁶ before melting. -3 The furnace was cleaned by introducing high-purity argon gas, and then the furnace cavity was evacuated to a vacuum of 5.0 × 10⁻⁶ Pa. -3 After being filled with high-purity argon again, the furnace was smelted. During the first smelting, the induction power was set to 300kW and the time was 30min. After the smelting was completed, a first ingot was obtained. Then, the first ingot was flipped and inverted for the second smelting. The induction power was set to 300kW and the time was 25min. After the smelting was completed, the furnace was cooled to room temperature to obtain a discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite ingot.

[0045] Figure 1 The discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite ingot prepared in Example 1 has a total weight of 7000g. As can be seen, the ingot has a good appearance and no obvious melting defects.

[0046] Figure 2 The microstructure of the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material prepared in Example 1 shows that the microstructure of the titanium-based composite material consists of α phase, a small amount of residual β phase, particulate TiC and fiber TiB.

[0047] Figure 3The phase analysis results of the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material prepared in Example 1 confirm that the phases contained in the microstructure of the titanium matrix composite material are α phase, β phase, TiC and TiB.

[0048] Example 2 The difference between this embodiment and Embodiment 1 is that the mass fraction of boron carbide (B4C) powder in this embodiment is 1.0%, and its weight is 70g. The remaining 6930g of material is the raw material required for the titanium alloy matrix. The process involves three melting stages. The first melting stage is set with an induction power of 340kW and a time of 26 minutes to obtain a primary ingot. The primary ingot is then flipped and inverted for a second melting stage, with the induction power set at 340kW and the time at 28 minutes to obtain a secondary ingot. The secondary ingot is then flipped and inverted for a third melting stage, with the induction power maintained at 260kW and the time shortened by 5 minutes compared to the first melting stage. After melting, the ingot is cooled in the furnace at a rate of 5~8℃ / min to below 30℃ before being removed from the furnace, resulting in a discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite ingot.

[0049] Figure 4 The discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite ingot prepared in Example 2 has a total weight of 7000g. As can be seen, the ingot has a good appearance and no obvious melting defects.

[0050] Figure 5 The microstructure of the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material prepared in Example 2 shows that the microstructure of the titanium-based composite material consists of α phase, a small amount of residual β phase, particulate TiC and fiber TiB.

[0051] Figure 6 The phase analysis results of the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material prepared in Example 2 confirm that the phases contained in the microstructure of the titanium matrix composite material are α phase, β phase, TiC and TiB.

[0052] Compared with Example 1, it can be seen that in the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material prepared in Example 2, the volume fraction of the reinforcing phases TiC and TiB is significantly increased.

[0053] Example 3 The difference between this embodiment and Embodiment 1 is that the content of each element in the alloy matrix is ​​as follows: Al: 7.0%, Zr: 7%, Sn: 4%, Mo: 1.2%, Nb: 0.8%, W: 1.2%, Si: 0.4%, O: 0.2%, C≤0.02%, N≤0.02%, H≤0.01%, with the balance being titanium, and the total of other unavoidable impurity elements ≤0.2%; the mass fraction of boron carbide (B4C) powder is 1.5%, with a weight of 105g, and the remaining 6895g is the raw material required for the titanium alloy matrix; The process involves two melting processes. The first melting process is set with an induction power of 260kW and a time of 36min to obtain a primary ingot. The primary ingot is then flipped and inverted for a second melting process, with the induction power set at 240kW and a time of 22min. After all melting processes are completed, the ingot is cooled in the furnace at a rate of 5~8℃ / min to below 30℃ before being removed from the furnace, resulting in a discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite ingot.

[0054] Example 4 The difference between this embodiment and Embodiment 1 is that the content of each element in the alloy matrix is ​​as follows: Al: 5.0%, Zr: 5%, Sn: 6%, Mo: 0.8%, Nb: 1.2%, W: 0.8%, Si: 0.2%, O: 0.1%, C≤0.02%, N≤0.02%, H≤0.01%, with the balance being titanium, and the total of other unavoidable impurity elements ≤0.2%; the mass fraction of boron carbide (B4C) powder is 2.0%, with a weight of 140g, and the remaining 6860g of material is the raw material required for the titanium alloy matrix.

[0055] In summary, as shown in Examples 1-4, for every 0.5% increase in the amount of B4C powder added, the total volume fraction of TiC and TiB in the prepared discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material increases by 1.2% to 1.5%. Figure 7 The tensile properties at 650°C, 700°C, and 750°C of the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composites prepared in Examples 1 and 2 were tested, confirming that the prepared discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composites have excellent high-temperature tensile strength, meeting the high-temperature service requirements of thermal structural components in new spacecraft and hypersonic vehicles.

[0056] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention.

[0057] It should be understood that the present invention is not limited to the content already described above, and various modifications and changes can be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material, characterized in that, According to mass percentage, the alloy matrix of the titanium-based composite material is composed of the following components: Al: 6%~8%, Zr: 5%~7%, Sn: 4%~6%, Mo: 0.8%~1.2%, Nb: 0.8%~1.2%, W: 0.8%~1.2%Mo, Si: 0.2%~0.4%, O: 0.1%~0.2%, C≤0.02%, N≤0.02%, H≤0.01%, with the balance being Ti, and other unavoidable individual impurity elements ≤0.05%, with the total impurities ≤0.2%; the discontinuous ceramic phase is obtained by adding B4C to the alloy matrix and reacting it with Ti, and the mass percentage of B4C is 0.5%~2%.

2. The discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material according to claim 1, characterized in that, The discontinuous ceramic phases are titanium carbide (TiC) and titanium boride (TiB).

3. A method for preparing the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material according to claim 1 or 2, characterized in that, Includes the following steps: Step 1: Prepare the matrix alloy raw material package by mixing the raw materials according to the mass percentage of each element in the alloy matrix and mixing them evenly. Step 2: Weigh out the B4C powder according to the mass percentage and prepare the reaction source material package; Step 3: The matrix alloy raw material package and the reaction source material package are smelted multiple times, cooled and then taken out of the furnace to obtain a discontinuous ceramic phase reinforced high temperature resistant titanium matrix composite material ingot.

4. The method for preparing the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material according to claim 3, characterized in that, In step 1, the raw materials include grade 0 sponge titanium, high-purity aluminum briquettes, high-purity aluminum foil, sponge zirconium, titanium-tin master alloy, aluminum-molybdenum master alloy, aluminum-niobium master alloy, aluminum-tungsten master alloy, and aluminum-silicon master alloy.

5. The method for preparing the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material according to claim 4, characterized in that, The titanium-tin master alloy is Ti80Sn, the aluminum-molybdenum master alloy is Al60Mo, the aluminum-niobium master alloy is Al75Nb, the aluminum-tungsten master alloy is Al50W, and the aluminum-silicon master alloy is Al10Si.

6. The method for preparing the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material according to claim 3, characterized in that, In step 2, the purity of the B4C powder is ≥99.9% and the average particle size is 20 micrometers.

7. The method for preparing the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material according to claim 3, characterized in that, In step 3, a vacuum induction levitation melting furnace is used for melting. Before melting, the furnace cavity of the vacuum induction levitation melting furnace is evacuated to a vacuum degree ≤ 5.0 × 10⁻⁶. -3 The furnace is cleaned by introducing argon gas with a purity ≥99.999% at a pressure of 0.08~0.12MPa and holding the pressure for 4~6 minutes. Then, the furnace cavity is evacuated again to a vacuum degree ≤5.0×10⁻⁶. -3 Pa, and finally high-purity argon gas is introduced to a pressure of 0.04~0.06MPa to form a protective melting atmosphere.

8. The method for preparing the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material according to claim 3, characterized in that, In step 3, a vacuum induction levitation melting furnace is used for melting: when the melting is performed twice, the induction power is set to 240~360kW and the time is 24~36min for the first melting to obtain a first ingot; the first ingot is flipped and inverted for a second melting, with the induction power set to 240~360kW and the time being 20~30min; after all melting is completed, the ingot is cooled to below 30℃ with the furnace at a cooling rate of 5~8℃ / min and then removed from the furnace to obtain a discontinuous ceramic phase reinforced high temperature resistant titanium matrix composite ingot.

9. The method for preparing the discontinuous ceramic phase reinforced high-temperature resistant titanium-based composite material according to claim 8, characterized in that, When the number of meltings is 3 or more, starting from the third melting, the power of the induction power supply for each melting is maintained at 240~360kW, and the time is shortened by 4~6min compared to the previous melting. After all meltings are completed, the furnace is cooled to below 30℃ with a cooling rate of 5~8℃ / min to obtain a discontinuous ceramic phase reinforced high temperature resistant titanium matrix composite ingot.

10. The application of the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material according to claim 1 or 2, or the discontinuous ceramic phase reinforced high-temperature resistant titanium matrix composite material prepared according to any one of the preparation methods of claims 3 to 9, in the thermal structural components of new spacecraft and hypersonic vehicles.

Images